Our objective is to examine the association between workers' exposures to the primary solvents used in commercial dry cleaning plants and the distribution of causes of death and mortality rates among those exposed. The specific aims will be: 1. Categorize each commercial dry cleaning plant in Oklahoma, between 1941-1984, by specific solvent use over time. 2. Identify a cohort of Oklahoma dry cleaning plant owner/operators and operators with known solent exposures and durations of exposure between 1941-1984. 3. Determine the Standardized Mortality Ratio (SMR) for all deaths and selected causes of death occurring between 1941-1984 to include cancer, kidney, lung, and liver cancer. 4. Estimate latency in cases of renal cell carcinoma. 5. Identify high risk subgroups for future measurement of actual exposure levels, nonfatal acute and chronic effects on the human kidney, and effects on reproductive outcome related to exposure to petroleum or synthetic solvents among Oklahoma dry cleaners. 6. Prpare a final report of the findings, analyses, and recommendations resulting from this study. The above objective and specific aims will be achieved by review of the yearly license application from 1941 to 1984 and other resources available at the Oklahoma Dry Cleaning Board. It is anticipated that a cohort of owners/operators totaling 5,000 individuals, (80-85% white males) representing 40% of the total population of risk will be identified. Each individual in the cohort will be categorized by solvent and durations of exposure from employment history. The number of plants with unknown solvent type is currently less than one per cent of the total. Among this cohort, age-time-solvent and duration of exposure specific SMR's for selected causes of death will be tabulated, latency periods, estimated and high risk subgroups identified. This research design will provide data to address the following research questions: 1. Is there any difference in the distribution of causes of death or mortality rates among owner/operators or operators of commercial plants dry cleaning plants when compared to all other death occurring in all U.S. white males, or white male Oklahomans between 1941 and 1984? 2. What is the influence, if any, of known specific solvent exposures and durations of exposure, in years, on the age and time specific distribution of causes of death and mortality rates in this population?